Recent developments in MRI applications to rheology and fluid mechanics.

Two recent developments using proton MRI velocimetry are reported, that concern both fields of rheology and of fluid mechanics. The first one is a way to get noticeable improvement in the signal-to-noise ratio during velocity measurements in a large-size 'Couette' rheometer. It opens a route to improve the study of complex or thixotrope fluids. The second one deals with the introduction of a model of concrete mixer inside the MRI facility. Thanks to synchronisation between movements of the model and MRI sequences, 3D velocity maps were obtained for a viscoplastic fluid inside the mixer. (C) 2004 Academie des sciences. Publie par Elsevier SAS. Tous droits reserves.